package com.valuedaas.schoolsafety.util;

import com.valuedaas.schoolsafety.common.Constants;
import org.apache.commons.lang3.StringUtils;
import org.springframework.util.DigestUtils;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;


public class SecurityUtil {

	public static String genMd5Password(String salt, String password) {
		byte[] bytes = (salt + "##" + password).getBytes();
		// String passwordMd5 = new String(DigestUtils.md5Digest(bytes));
		String passwordMd5 = DigestUtils.md5DigestAsHex(bytes);
		return passwordMd5;
	}

	public static String encodeRememberToken(String account, String pwdmd5) {
		String data = String.format("%s&&%s&&remember", new Object[] { account, pwdmd5 });
		String token = encrypt(data, Constants.ENCODE_DES_KEY, "DES");
		return token;
	}

	public static String[] decodeRememberToken(String token) {
		String decodeStr = decrypt(token, Constants.ENCODE_DES_KEY, "DES");
		if(StringUtils.isEmpty(decodeStr)){
		    return null;
        }
		String[] strArr = decodeStr.split("\\&\\&");
		return strArr;
	}

	/**
	 * 对数据源进行加密
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥
	 * @param name
	 *            算法的名称
	 * @return 返回加密后的数据
	 * @throws Exception
	 *             异常
	 */
	public static byte[] encrypt(byte[] src, byte[] key, String name) throws Exception {
		SecretKeySpec securekey = new SecretKeySpec(key, name);
		// Cipher对象实际完成加密操作
		Cipher cipher = Cipher.getInstance(name);
		// 用密匙初始化Cipher对象
		cipher.init(Cipher.ENCRYPT_MODE, securekey);
		// 现在，获取数据并加密
		// 正式执行加密操作
		return cipher.doFinal(src);
	}

	/**
	 * 对加密的数据源进行解密
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥
	 * @param name
	 *            算法的名称
	 * @return 返回解密后的原始数据
	 * @throws Exception
	 *             异常
	 */
	public static byte[] decrypt(byte[] src, byte[] key, String name) throws Exception {
		SecretKeySpec securekey = new SecretKeySpec(key, name);
		// Cipher对象实际完成解密操作
		Cipher cipher = Cipher.getInstance(name);
		// 用密匙初始化Cipher对象
		cipher.init(Cipher.DECRYPT_MODE, securekey);
		// 现在，获取数据并解密
		// 正式执行解密操作
		return cipher.doFinal(src);
	}

	/**
	 * 二行制转字符串
	 * 
	 * @param bytes
	 *            二进制数组
	 * @return 字符串
	 */
	public static String bytes2HexString(byte[] bytes) {
		String hs = null;
		if (bytes != null) {
			final int size = bytes.length;
			if (size > 0) {
				StringBuilder sb = new StringBuilder();
				for (int i = 0; i < size; i++) {
					String tmp = (Integer.toHexString(bytes[i] & 0XFF));
					if (tmp.length() == 1) {
						sb.append("0" + tmp);
					} else {
						sb.append(tmp);
					}
				}
				hs = sb.toString().toUpperCase();
			}
		}
		return hs;
	}

	public static byte[] hex2byte(byte[] b) {
		if ((b.length % 2) != 0) {
			return null;
		}
		byte[] b2 = new byte[b.length / 2];
		for (int n = 0; n < b.length; n += 2) {
			String item = new String(b, n, 2);
			b2[n / 2] = (byte) Integer.parseInt(item, 16);
		}
		return b2;
	}

	/**
	 * 十六进位格式字符串转二进制流。
	 *
	 * @param hs
	 *            十六进位格式字符串
	 * @return byte[]
	 */
	public static byte[] hexString2Bytes(String hs) {
		byte[] bytes = null;
		if (hs != null) {
			final int size = (hs.length()) / 2;
			if (size > 0) {
				bytes = new byte[size];
				for (int i = 0; i < size; i++) {
					String hsByte = hs.substring(i * 2, i * 2 + 2);
					byte b = 0;
					try {
						b = (byte) (Integer.parseInt(hsByte, 16));
					} catch (NumberFormatException e) {
						b = 0;
					}
					bytes[i] = b;
				}
			}
		}
		return bytes;
	}

	/**
	 * 字符串解密
	 * 
	 * @param data
	 *            字符串加密数据
	 * @param key
	 *            密钥
	 * @param name
	 *            算法名称
	 * @return 解密字符串
	 */
	public static String decrypt(String data, String key, String name) {
		try {
			return new String(decrypt(hex2byte(data.getBytes()), string2Bytes(key), name));
		} catch (Exception e) {

		}
		return null;
	}

	/**
	 * 字符串解密
	 * 
	 * @param data
	 *            符串加密数据
	 * @param key
	 *            密钥
	 * @param name
	 *            算法名称
	 * @return 解密字符串
	 */
	public static String decrypt(String data, byte[] key, String name) {
		try {
			return new String(decrypt(hex2byte(data.getBytes()), key, name));
		} catch (Exception e) {

		}
		return null;
	}

	/**
	 * 把字符串转化成 Unicode Bytes.
	 * 
	 * @param s
	 *            字符串
	 * @return byte[]
	 */
	public static byte[] string2Bytes(String s) {
		byte[] bytes = null;
		if (s != null) {
			try {
				bytes = s.getBytes("utf-8");
			} catch (UnsupportedEncodingException e) {
				e.printStackTrace();
			}
		}
		return bytes;
	}

	/**
	 * 根据 Unicode Bytes 构造字符串.
	 * 
	 * @param bytes
	 *            byte[]
	 * @return String
	 */
	public static String bytes2String(byte[] bytes) {
		String s = null;
		if (bytes != null) {
			try {
				s = new String(bytes, "utf-8");
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		return s;
	}

	/**
	 * 字符串加密
	 * 
	 * @param data
	 *            字符串数据
	 * @param key
	 *            密钥
	 * @param name
	 *            算法名称
	 * @return String
	 */
	public static String encrypt(String data, byte[] key, String name) {
		try {
			return bytes2HexString(encrypt(data.getBytes(), key, name));
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 字符串加密
	 * 
	 * @param data
	 *            字符串数据
	 * @param key
	 *            密钥
	 * @param name
	 *            算法名称
	 * @return String
	 */
	public static String encrypt(String data, String key, String name) {
		try {
			return bytes2HexString(encrypt(data.getBytes(), string2Bytes(key), name));
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	public static void main(String[] args) {
		System.out.println(genMd5Password("15566668888", "123456"));
	}

}
